Method and System for Document Retrieval with Selective Document Comparison

ABSTRACT

This invention discloses a novel system and method for displaying electronic documents on remote devices and enabling collaborative editing where the system upon a request by a user to access a document, automatically determines the latest version of a document that the person had accessed and also whether a newer version had been created. The invention also merges parallel changes that have not been viewed by the user into the comparison result. The invention also includes running a comparison on the two versions and presenting the result to the user.

FIELD OF INVENTION

The present invention generally relates to the field of digital documentreview. More particularly, the present invention relates to methods andsystems for detecting changes and/or differences between an originaldocument and a modified version of the document.

BACKGROUND

In several scenarios, one or more users may go through multiplerevisions of a document to improve the content and presentability of thedocument contents. As a result of their being more than one userauthorized to access and modify a document, other users may becomeconfused when requesting to see a document if they are not aware thatthe document has changed and how. In doing so, a user may wish tocompare a latest version of the document with a prior version todetermine the changes that have been made to the latest version. Otherlimitations of existing or prior systems will become apparent to thoseof skill in the art upon reading the following Detailed Description.

At least one embodiment of this invention pertains to a documentmanagement service that enables a user to request a document from theservice to be delivered to a remote computer and have the servicecompare the last version of the document that the user accessed with thelatest version and to deliver a display document showing those changesThe document management service may run as a standalone service on auser's computing device or, in some instances, may run as a web serviceon a remote server. In either scenario, the document management servicereceives as input a request for particular document that a user wishesto see. The service determines whether the current version of thedocument supersedes the version of the document that the requesting userhas previously seen. Subsequent to receiving the requests, the compareservice generates a comparison document by identifying differencesbetween the latest version of the document and the version that therequesting user has previously seen. The compare service delivers to theuser's computer the comparison result. These and other objects, featuresand characteristics of the present invention will become more apparentto those skilled in the art from a study of the following detaileddescription in conjunction with the appended claims and drawings, all ofwhich form a part of this specification. It should be understood thatthe description and specific examples are intended for purposes ofillustration only and not intended to limit the scope of the presentdisclosure.

DESCRIPTION OF THE FIGURES

The headings provided herein are for convenience only and do notnecessarily affect the scope or meaning of the claimed invention. In thedrawings, the same reference numbers and any acronyms identify elementsor acts with the same or similar structure or functionality for ease ofunderstanding and convenience. To easily identify the discussion of anyparticular element or act, the most significant digit or digits in areference number refer to the Figure number in which that element isfirst introduced (e.g., element 204 is first introduced and discussedwith respect to FIG. 2).

01. Flow chart depicting the basic architecture of the process.02. Example access history data table associated with a document.03. Example document revision history schematic04. Example document revision history as a tree structure.

DETAILED DESCRIPTION

Various examples of the invention will now be described. The followingdescription provides specific details for a thorough understanding andenabling description of these examples. One skilled in the relevant artwill understand, however, that the invention may be practiced withoutmany of these details. Likewise, one skilled in the relevant art willalso understand that the invention can include many other features notdescribed in detail herein. Additionally, some well-known structures orfunctions may not be shown or described in detail below, so as to avoidunnecessarily obscuring the relevant description. The terminology usedbelow is to be interpreted in its broadest reasonable manner, eventhough it is being used in conjunction with a detailed description ofcertain specific examples of the invention. Indeed, certain terms mayeven be emphasized below; however, any terminology intended to beinterpreted in any restricted manner will be overtly and specificallydefined as such in this Detailed Description section.

The method and system operates on one or more computers, typically usingone or more servers and one or more remote user's computing devices. Acustomer's device can be a personal computer, mobile phone, mobilehandheld device like a Blackberry™ or iPhone™ or a tablet device likethe iPad™ or Galaxy™ or any other kind of computing device a user canuse to view and edit an electronic document. The user devices areoperatively connected to the remote server using a data network. Theinvention does not require that the data network be in continuouscontact with the remote file server. The invention works in conjunctionwith a document collaborative editing system (CES) or documentmanagement systems, (DMS) or both. For brevity, references to the DMS inthe disclosure may disclose processes that may be performed by the CESor the CES in combination with the DMS. The system can be embodied in aclient/server architecture, whereby an executable code operates on theuser's remote device and interacts with processes operating on a server.In other embodiments, the same system can be running on the user'sremote device by means of scripts or apps that are downloaded andexecuted within an Internet web-browser.

The user's remote computer is operatively connected to a datacommunication network, typically the Internet. This may be directly orindirectly through another network, for example a telephone network or aprivate data network. The user operates a client software on theircomputing device that communicates with the server that operates theprocess as a service, or the server that delivers documents for editingor review, that is the DMS or CES.

When the client requests to view a document available on the DMS, therequest is received and processed on the DMS. In this case, the user'sdevice may select a document title from a graphical user interfacedisplayed on the screen of the device. The DMS maintains all of therevisions of the document in its data storage repository. Each time theCES saves a new version, that is a new computer file. That new filetypically has a different filename than the prior version. The systemalso keeps track of the date and time that the version was stored. Thesystem maintains a separate database that keeps track of each userauthorized to access the document on the CES and their access of thedocument. For example, FIG. 2 shows a data table assigned to a givendocument, with a Document ID. That table shows a list of user ID's andthen the time they accessed the document, which version of the documentand whether it was for a read or a write. When a user with an identifierof USERID accesses the document referred to as DOCUMENT ID, then a newrow in the table is created. That row is populated with the time stampfor the access, and which VERSION ID associated with the DOCUMENT ID wasaccessed. If the access was to read the document then the R/W flag isset to R. For each VERSION ID, there is a corresponding file pointerthat refers to the data file containing that version of the document.While a simple data table is presented, other data structureorganizations may be used to store the access history of the document.This access history is used by the process to determine which revisionsof the document a particular user has not seen.

Returning to the user interface, the user can select a document toreview by name. The system can then determine which version to deliver.For example, it may be that the user wishes to see the last version ofthe document they worked on. However, as shown in FIG. 3, in the case ofa user 1, who creates a document and releases it into CES environment,that document may go through several revisions instituted by severalpeople in the group. In this example, the document version 1 (301) getsrevised by user 2 (302) who thereby creates version 2 of the document(303). FIG. 4 shows the situation where a document gets revised suchthat there are more than one sets of revision history. FIG. 2 shows howeach version has a VERSIONID that can be stored in the activitydatabase. So in the example of FIG. 3, the USER1 entry has a W entry onthe creation of VERSION 1 of the document. In the next row, USER2 has anentry for the creation of VERSION 2 of the document. Similarly, otherusers can have entries showing that they accessed a particular versionof the document for reading, which would be indicated by an R in thelast column. A user may have more than one row in the table: this wouldindicate the user accessing the document an additional time.

In the typical system, the user logs into a CES using a username andpassword, or similar computer security mechanism. The CES confirms theidentity of the user in typical fashion, for example, by looking in adatabase to obtain a password string corresponding to the username andconfirming that they match. In any case, the system obtains a USERID forthat user. Through a typical graphical user interface, the user canrequest to see a document. This can be by means of opening a directorylisting, accessing a most recently used list, or using a typicaldocument management system tool that lists documents associated with aclient or project. As a result of such a request, the system thenobtains a DOCUMENT ID. The DOCUMENT ID may be a filename or otheridentifier associated with the set of files constituting a document andits revisions, as indicated in FIGS. 3 and 4.

The system then uses the access history associated with the DOCUMENT IDto determine the latest VERSION ID that the user has accessed. As shownin FIG. 2, the system can search for the lowest row that the USERID canbe found. Then it can retrieve from the table the VERSION ID. The systemcan then continue down the table rows looking for a newer VERSION ID. Ifone is found, then by definition, that VERSION ID is later than the onethe user accessed. Otherwise, the same USERID would occupy that row.Practitioners will recognize that other data structures may be used tostore the dependencies of the access history and other kinds ofalgorithms may be used to identify the last version that a user hasaccessed and whether there is a later version.

Upon determining the version of the document that the user last accessedand the latest version, the system can present the user the choice ofeither opening the older document, opening the newer document, oropening a comparison document that compares the later version of thedocument to the version the user had last seen. This last step requiresrunning a comparison between the two versions of the document. Documentcomparison may be accomplished using a string matching algorithm, thatis, one that begins trying to match the character strings in a documentfile to the character strings in the other document file. Documentcomparison can be further enhanced by ignoring certain characters, forexample, spaces, new line characters and certain formatting characters.Document comparison can be even further enhanced by creating datastructures out of the document text that model the document as ahierarchy of component paragraphs and sections, and comparing thesefirst, to account for paragraphs being moved within the document, andthen only showing comparisons of the text in the paragraph.

Once the compared document is presented to the user, the user can makechanges to the document and save it as yet a newer version. In this casethe system will generate a new data file comprising the new version isof the document is created and a new VERSION ID. When a new version ofthe document is created, it's a distinct document data file. The USERID,the new VERSION ID and the W entry are entered into the access historytable. A pointer to the file is also included into the table.Alternatively, the user may simply read the document with no changes. Inthe first case, a new row entry is made in the access history table thatindicates a new VERSION ID and a W (write) access and the file pointerto the new file. In the second case, the new row entry is made with thesame VERSION ID entered and a R (read) access.

In one embodiment, the system works with a document where for anyversion of the document, there is one parent version and one childversion, except for the first version and the last version. See FIG. 3.In this embodiment, the latest version of the document is the last inthe series, that is, the newest version number or VERSION ID. In anotherembodiment, the system may have versions of the document where adocument may have one parent, but more than one child version. Thisoccurs when a version of the document is opened by two different userswho then save their versions of the document as distinct versions. SeeFIG. 4.

In this second embodiment, there arises the determination of what thelatest version of the document is, for the purposes of running thecomparison. All of the candidate latest versions would appear as leafnodes in the schematic shown in FIG. 4. Each node in the tree hierarchyrepresents a version of the document. Each edge linking the nodesrepresents a user that modified a parent version to create a childversion. Selecting from this set can be accomplished in several ways,depending on the utility being sought.

-   -   1. The simplest approach is to select the VERSIONID with the        latest time-stamp. In this case, the system will work down the        access history table looking for the row. A W (write) in        particular the row that has the latest access time stamp. The        VERSION ID and file pointer for that row is used to retrieve the        document.    -   2. Another approach is to consider the selection of the version        akin to selecting a leaf node on the basis of the path from the        initial version (or root node) to the leaf. In this case, the        leaf node that is on a path that includes the requesting USERID        can be selected. This would entail working through the access        history keeping track of the hierarchical structure, typically        by means of using a stack to process the hierarchical structure.    -   3. In yet another approach, the selection can be the leaf node        that is the end point of a path that includes the originator of        the document (other than the first or root version). In this        case, the system looks for the path where an interim version was        represented by a entry in the table where the USERID matches the        USERID associated with the first VERSIONID.    -   4. In yet another approach, the selection can be the leaf node        that is the endpoint of a path that includes a version created        by a USERID associated with some pre-determined seniority value.        In this example, the USERID of the version creator may be a        senior manager that is determined to be sufficiently important        as to have some predetermined value associated with their        USERID. Each time the system tests a node, the system can        retrieve this seniority value from a database that stores        information about the USERID, and can compare that seniority        value against some predetermined value. In yet another        embodiment, the user making the request for the document can        select or input the seniority value to be used for that        comparison.    -   5. In yet another approach, the leaf node that is a member of a        path that contains a version node that is associated with a        preference value that meets a pre-determined value. For example,        a senior manager in a document management system may select a        version and input a selection that tells the system the “use        this version”. This value can be stored in another column of the        access history table. However, that version may be revised        again, in which case the leaf node that is downstream from that        preferential selection may be the appropriate version to use for        the comparison.    -   6. In yet another approach, the requesting user can select which        of the leaf versions to use. In one embodiment, the system        analyzes the access history data to determine which VERSION IDs        have no child versions. The user interface presents a        hierarchical structure, similar to FIG. 4, and the user can view        for each node, the author of that version and its time stamp.        From that presentation, the user can input a selection of one of        the leaf nodes as the latest version for the comparison.

In yet another embodiment, the features disclosed herein can be arrangedso that the system performs the following steps:

1. When a user opens a file from either the a web app or desktopapplication, and

-   -   If there has been a new version of this file, and    -   Posted by anyone other than this user, and    -   Later in time than when the file was last viewed by this user,        then        2. The system asks the user if they would like to see what's new        in the file.        3. If the user's responds in the affirmative the system:    -   Compares the last version they viewed with the most recent        version, and    -   Produces a comparison report that highlights the changes.        4. The user may then save, download, forward or comment on the        comparison report.        5. If the user returns to the file view again from either user        interface, and the version has not changed again, regardless of        whether or not they ran the report on the previous visit, the        system does not ask the user because the activity data indicates        that they have now seen the latest version. In yet another        embodiment, the system also determines whether the latest second        version has at least one related version in the tree structure        relationship where such related version is not an ancestor        document to the second version, and in dependence thereon,        selecting at least one of the related versions, merging the        changes in the at least one related versions into the second        latest version in order to cause the comparison presented to the        requesting user to contain a compilation of the merged changes.

Operating Environment:

Those skilled in the relevant art will appreciate that the invention canbe practiced with other communications, data processing, or computersystem configurations, including: wireless devices, Internet appliances,hand-held devices (including personal digital assistants (PDAs)),wearable computers, all manner of cellular or mobile phones,multi-processor systems, microprocessor-based or programmable consumerelectronics, set-top boxes, network PCs, mini-computers, mainframecomputers, and the like. Indeed, the terms “computer,” “server,” and thelike are used interchangeably herein, and may refer to any of the abovedevices and systems.

In some instances, especially where the mobile computing device 104 isused to access web content through the network 110 (e.g., when a 3G oran LTE service of the phone 102 is used to connect to the network 110),the network 110 may be any type of cellular, IP-based or convergedtelecommunications network, including but not limited to Global Systemfor Mobile Communications (GSM), Time Division Multiple Access (TDMA),Code Division Multiple Access (CDMA), Orthogonal Frequency DivisionMultiple Access (OFDM), General Packet Radio Service (GPRS), EnhancedData GSM Environment (EDGE), Advanced Mobile Phone System (AMPS),Worldwide Interoperability for Microwave Access (WiMAX), UniversalMobile Telecommunications System (UMTS), Evolution-Data Optimized(EVDO), Long Term Evolution (LTE), Ultra Mobile Broadband (UMB), Voiceover Internet Protocol (VoIP), Unlicensed Mobile Access (UMA), etc.

The user's computer may be a laptop or desktop type of personalcomputer. It can also be a cell phone, smart phone or other handhelddevice, including a tablet. The precise form factor of the user'scomputer does not limit the claimed invention. Examples of well knowncomputing systems, environments, and/or configurations that may besuitable for use with the invention include, but are not limited to,personal computers, server computers, hand-held, laptop or mobilecomputer or communications devices such as cell phones and PDA's,multiprocessor systems, microprocessor-based systems, set top boxes,programmable consumer electronics, network PCs, minicomputers, mainframecomputers, distributed computing environments that include any of theabove systems or devices, and the like.

The system and method described herein can be executed using a computersystem, generally comprised of a central processing unit (CPU) that isoperatively connected to a memory device, data input and outputcircuitry (I/O) and computer data network communication circuitry. Avideo display device may be operatively connected through the I/Ocircuitry to the CPU. Components that are operatively connected to theCPU using the I/O circuitry include microphones, for digitally recordingsound, and video camera, for digitally recording images or video. Audioand video may be recorded simultaneously as an audio visual recording.The I/O circuitry can also be operatively connected to an audioloudspeaker in order to render digital audio data into audible sound.Audio and video may be rendered through the loudspeaker and displaydevice separately or in combination. Computer code executed by the CPUcan take data received by the data communication circuitry and store itin the memory device. In addition, the CPU can take data from the I/Ocircuitry and store it in the memory device. Further, the CPU can takedata from a memory device and output it through the I/O circuitry or thedata communication circuitry. The data stored in memory may be furtherrecalled from the memory device, further processed or modified by theCPU in the manner described herein and restored in the same memorydevice or a different memory device operatively connected to the CPUincluding by means of the data network circuitry. The memory device canbe any kind of data storage circuit or magnetic storage or opticaldevice, including a hard disk, optical disk or solid state memory.

The computer can display on the display screen operatively connected tothe I/O circuitry the appearance of a user interface. Various shapes,text and other graphical forms are displayed on the screen as a resultof the computer generating data that causes the pixels comprising thedisplay screen to take on various colors and shades. The user interfacealso displays a graphical object referred to in the art as a cursor. Theobject's location on the display indicates to the user a selection ofanother object on the screen. The cursor may be moved by the user bymeans of another device connected by I/O circuitry to the computer. Thisdevice detects certain physical motions of the user, for example, theposition of the hand on a flat surface or the position of a finger on aflat surface. Such devices may be referred to in the art as a mouse or atrack pad. In some embodiments, the display screen itself can act as atrackpad by sensing the presence and position of one or more fingers onthe surface of the display screen. When the cursor is located over agraphical object that appears to be a button or switch, the user canactuate the button or switch by engaging a physical switch on the mouseor trackpad or computer device or tapping the trackpad or touchsensitive display. When the computer detects that the physical switchhas been engaged (or that the tapping of the track pad or touchsensitive screen has occurred), it takes the apparent location of thecursor (or in the case of a touch sensitive screen, the detectedposition of the finger) on the screen and executes the processassociated with that location. As an example, not intended to limit thebreadth of the disclosed invention, a graphical object that appears tobe a 2 dimensional box with the word “enter” within it may be displayedon the screen. If the computer detects that the switch has been engagedwhile the cursor location (or finger location for a touch sensitivescreen) was within the boundaries of a graphical object, for example,the displayed box, the computer will execute the process associated withthe “enter” command. In this way, graphical objects on the screen createa user interface that permits the user to control the processesoperating on the computer.

The system is typically comprised of a central server that is connectedby a data network to a user's computer. The central server may becomprised of one or more computers connected to one or more mass storagedevices. The precise architecture of the central server does not limitthe claimed invention. In addition, the data network may operate withseveral levels, such that the user's computer is connected through afire wall to one server, which routes communications to another serverthat executes the disclosed methods. The precise details of the datanetwork architecture does not limit the claimed invention.

A server may be a computer comprised of a central processing unit with amass storage device and a network connection. In addition a server caninclude multiple of such computers connected together with a datanetwork or other data transfer connection, or, multiple computers on anetwork with network accessed storage, in a manner that provides suchfunctionality as a group. Further, a server may be virtual, wherebyseveral software instances each operating as an independent server arehoused in the same hardware computer. Practitioners of ordinary skillwill recognize that functions that are accomplished on one server may bepartitioned and accomplished on multiple servers that are operativelyconnected by a computer network by means of appropriate inter processcommunication. In addition, the access of the website can be by means ofan Internet browser accessing a secure or public page or by means of aclient program running on a local computer that is connected over acomputer network to the server. A data message and data upload ordownload can be delivered over the Internet using typical protocols,including TCP/IP, HTTP, SMTP, RPC, FTP or other kinds of datacommunication protocols that permit processes running on two remotecomputers to exchange information by means of digital networkcommunication. As a result a data message can be a data packettransmitted from or received by a computer containing a destinationnetwork address, a destination process or application identifier, anddata values that can be parsed at the destination computer located atthe destination network address by the destination application in orderthat the relevant data values are extracted and used by the destinationapplication.

The invention may also be practiced in distributed computingenvironments where tasks are performed by remote processing devices thatare linked through a communications network. In a distributed computingenvironment, program modules may be located in both local and remotecomputer storage media including memory storage devices. Practitionersof ordinary skill will recognize that the invention may be executed onone or more computer processors that are linked using a data network,including, for example, the Internet. In another embodiment, differentsteps of the process can be executed by one or more computers andstorage devices geographically separated by connected by a data networkin a manner so that they operate together to execute the process steps.In one embodiment, a user's computer can run an application that causesthe user's computer to transmit a stream of one or more data packetsacross a data network to a second computer, referred to here as aserver. The server, in turn, may be connected to one or more mass datastorage devices where the database is stored. The server can execute aprogram that receives the transmitted packet and interpret thetransmitted data packets in order to extract database query information.The server can then execute the remaining steps of the invention bymeans of accessing the mass storage devices to derive the desired resultof the query. Alternatively, the server can transmit the queryinformation to another computer that is connected to the mass storagedevices, and that computer can execute the invention to derive thedesired result. The result can then be transmitted back to the user'scomputer by means of another stream of one or more data packetsappropriately addressed to the user's computer.

Computer program logic implementing all or part of the functionalitypreviously described herein may be embodied in various forms, including,but in no way limited to, a source code form, a computer executableform, and various intermediate forms (e.g., forms generated by anassembler, compiler, linker, or locator.) Source code may include aseries of computer program instructions implemented in any of variousprogramming languages (e.g., an object code, an assembly language, or ahigh-level language such as FORTRAN, C, C++, JAVA, or HTML or scriptinglanguages that are executed by Internet web-browsers) for use withvarious operating systems or operating environments. The source code maydefine and use various data structures and communication messages. Thesource code may be in a computer executable form (e.g., via aninterpreter), or the source code may be converted (e.g., via atranslator, assembler, or compiler) into a computer executable form.

The invention may be described in the general context ofcomputer-executable instructions, such as program modules, beingexecuted by a computer. Generally, program modules include routines,programs, objects, components, data structures, etc., that performparticular tasks or implement particular abstract data types. Thecomputer program and data may be fixed in any form (e.g., source codeform, computer executable form, or an intermediate form) eitherpermanently or transitorily in a tangible storage medium, such as asemiconductor memory device (e.g., a RAM, ROM, PROM, EEPROM, orFlash-Programmable RAM), a magnetic memory device (e.g., a diskette orfixed hard disk), an optical memory device (e.g., a CD-ROM or DVD), a PCcard (e.g., PCMCIA card), or other memory device. The computer programand data may be fixed in any form in a signal that is transmittable to acomputer using any of various communication technologies, including, butin no way limited to, analog technologies, digital technologies, opticaltechnologies, wireless technologies, networking technologies, andinternetworking technologies. The computer program and data may bedistributed in any form as a removable storage medium with accompanyingprinted or electronic documentation (e.g., shrink wrapped software or amagnetic tape), preloaded with a computer system (e.g., on system ROM orfixed disk), or distributed from a server or electronic bulletin boardover the communication system (e.g., the Internet or World Wide Web.) Itis appreciated that any of the software components of the presentinvention may, if desired, be implemented in ROM (read-only memory)form. The software components may, generally, be implemented inhardware, if desired, using conventional techniques.

The described embodiments of the invention are intended to be exemplaryand numerous variations and modifications will be apparent to thoseskilled in the art. All such variations and modifications are intendedto be within the scope of the present invention as defined in theappended claims. Although the present invention has been described andillustrated in detail, it is to be clearly understood that the same isby way of illustration and example only, and is not to be taken by wayof limitation. It is appreciated that various features of the inventionwhich are, for clarity, described in the context of separate embodimentsmay also be provided in combination in a single embodiment. Conversely,various features of the invention which are, for brevity, described inthe context of a single embodiment may also be provided separately or inany suitable combination. It is appreciated that the particularembodiment described in the specification is intended only to provide anextremely detailed disclosure of the present invention and is notintended to be limiting.

It should be noted that the flow diagrams are used herein to demonstratevarious aspects of the invention, and should not be construed to limitthe present invention to any particular logic flow or logicimplementation. The described logic may be partitioned into differentlogic blocks (e.g., programs, modules, functions, or subroutines)without changing the overall results or otherwise departing from thetrue scope of the invention. Oftentimes, logic elements may be added,modified, omitted, performed in a different order, or implemented usingdifferent logic constructs (e.g., logic gates, looping primitives,conditional logic, and other logic constructs) without changing theoverall results or otherwise departing from the true scope of theinvention.

Also, while processes or blocks are at times shown as being performed inseries, these processes or blocks may instead be performed orimplemented in parallel, or may be performed at different times.

What is claimed:
 1. A method for providing a user operating a remotecomputer access to a document embodied in at least two versions storedon a server comprising: receiving from a user a request for access tothe document; by inspecting a data structure representing the accesshistory of the document, making a first determination of a first versionof the document that is the latest version viewed by the requestinguser, a second determination whether the document is embodied in asecond version saved by a user other than the requesting user that isassociated with either a storage time or a version indicator that islater than the first version or both; in dependence on the seconddetermination, transmitting a query to the requesting user; receivingfrom the user a response to the query; and in dependence on theresponse, generating a comparison between the first version and thesecond version of the document.
 2. The method of claim 1 furthercomprising generating a comparison report that highlights the changesbetween the first version and the second version.
 3. The method of claim2 further comprising: transmitting the comparison report to therequesting user; and updating the document access history data structureto indicate that the requesting user has viewed the second version ofthe document.
 4. The method of claim 1 where the making of the firstdetermination is comprised of: Selecting the second version of thedocument by selecting a leaf node in a tree-structured representation ofa hierarchy of versions of the document.
 5. The method of claim 1 wherethe transmitting step is comprised of transmitting data representing adiagram of the tree-structured representation of additional versions ofthe document in order to cause that representation to be displayed by aremote computer operated by the user; and receiving a command from therequesting user that embodies a selection of a version of the document.6. The method of claim 1 further comprising a determination whether thelatest second version has at least one related versions in a treestructure relationship where such related version is not an ancestordocument to the second version, and in dependence thereon, selecting atleast one of the related versions, merging the changes in the at leastone related versions into the second latest version in order to causethe comparison presented to the requesting user to contain a compilationof the merged changes.
 7. A computer system for providing a useroperating a remote computer access to a document embodied in at leasttwo versions stored on a server comprising: a component adapted forreceiving from a user a request for access to the document; a componentadapted for inspecting a data structure representing the access historyof the document, a component adapted for making a first determination ofa first version of the document that is the latest version viewed by therequesting user, a component adapted for making a second determinationwhether the document is embodied in a second version saved by a userother than the requesting user that is associated with either a storagetime or a version indicator that is later than the first version orboth; a component adapted for transmitting a query to the requestinguser in dependence on the second determination, a component adapted forreceiving from the user a response to the query; a component adaptedfor, in dependence on the response, generating a comparison between thefirst version and the second version of the document.
 8. The computersystem of claim 7 further comprising a component adapted for generatinga comparison report that highlights the changes between the firstversion and the second version.
 9. The computer system of claim 8further comprising: a component adapted for transmitting the comparisonreport to the requesting user; and a component adapted for updating thedocument access history data structure to indicate that the requestinguser has viewed the second version of the document.
 10. The system ofclaim 7 further where the component adapted to make the firstdetermination is further adapted to: Select the second version of thedocument by selecting a leaf node in a tree-structured representation ofa hierarchy of versions of the document.
 11. The system of claim 7 wherethe transmitting component is further adapted to transmit datarepresenting a diagram of the tree-structured representation ofadditional versions of the document in order to cause thatrepresentation to be displayed by a remote computer operated by theuser; and receive a command from the requesting user that embodies aselection of a version of the document.
 12. The system of claim 7further comprising a component adapted to determine whether the latestsecond version has at least one related versions in a tree structurerelationship where such related version is not an ancestor document tothe second version, and in dependence thereon, select at least one ofthe related versions, and merge the changes in the at least one relatedversions into the second latest version in order to cause the comparisonpresented to the requesting user to contain a compilation of the mergedchanges.